The raids in Hama came after Syrian army defectors attacked an army checkpoint the previous day, killing eight soldiers in that attack, according to the British-based Syrian Observatory for Human Rights.

Assad is facing severe isolation stemming from his crackdown on an 8-month-old uprising, which appears to be spiraling out his control. Attacks by army defectors are growing, and world leaders are looking at possibilities for a Syrian regime without Assad.

The latest blow came from the Arab League, which on Wednesday suspended Damascus and threatened economic sanctions if the regime continues to violate an Arab-brokered peace plan.

Germany, Britain and France are pressing for a U.N. resolution that would strongly condemn Syria's human rights violations. The three European countries decided to move ahead with the General Assembly resolution after the Arab League confirmed its suspension.

"We hope it will show Assad just how isolated he is," Germany's U.N. Ambassador Peter Wittig said of the resolution.

Russia and China have stood by Damascus amid concerns that the downfall of Assad would be a severe blow to their interests in the Middle East. In October, they vetoed a U.N. Security Council resolution that threatened sanctions against Syria if it didn't end its crackdown.

But on Thursday, Chinese Foreign Ministry spokesman Liu Weimin appeared to suggest China might support a resolution in the future.

"It depends on whether these actions will help to resolve the tensions in Syria and facilitate the resolution of disputes through political dialogue," he said.

Also Thursday, Russian and European Union officials were holding talks on Syria and other issues in Moscow.

The U.N. estimates Assad's crackdown has killed more than 3,500 people since the uprising began in March.

The growing calls for Assad's ouster are a severe blow to a family dynasty that has ruled Syria for four decades — and any change to the leadership could transform some of the most enduring alliances in the Middle East and beyond.

Syria's tie to Iran is among the most important relationships in the Middle East, providing the Iranians with a foothold on Israel's border and a critical conduit to Tehran-backed Hezbollah in Lebanon and the Palestinian Hamas in Gaza.